Ro 45-2081 is a recombinent molecule that consists of the complete extracellular domain of the human 55 KD TNF alpha receptor and an immunoglobulin IgG heavy chain sequence. It is designed to have a longer in vivo half-life and higher TNF neutralizing capability than a natural TNF inhibitor. Previous studies have utilized intravenous infusion in patients with rheumatoid arthritis and have demonstrated salutory effects. The current study will utilize a subcutaneous route of administration either given alone or in combination with methotrexate and will evaluate the clinical and functional manifestations of rheumatoid arthritis over a 12 week period.